Improvement in stereoscopic cameras



W. HARRIS.

Steraoscopic Cameras. Nov.15.l`,9-72. Pa'xemedmnmsnan.

X1 mm UNITED STATES TARREET HARRIS, OF DANVILLE, VERMONT.

IWIPRGJ'ENIENT IN STEREOSCOPIC CAMERAS.

Specification forming part of Letters Patent No. 151,972, dated June 16, 1874; application tiled February 3, 1874.

CASE B.

To all whom it may concern:

Be it known that I, WARREN HAnRis, of Danville, in the county of Caledonia land State of Vermont, have invented a certain Improvement in Stereoscopic Camera-s, ot which the following is a specification v The objectot' my invention is to take positive and nega-tive stereoscopic portraits and views which shall not require transposition, by the combination oi'two reilectors with the two object-glasses of a stereoscopic camera. .in such a manner as to cause the light to i'orm each of the two images without lateral inversion, (when viewed from the side next the leus,) and without causing' the rays which form one image to cross those which form the other after reflection.

Figure l is aI perspective view. vertical section.

A is' the front board of an ordinar5Y stereoscopic camera, with the object-glasses l5 C in their usual positions. D is a reflector, close in front ofthe object-glass B, at an angle of forty-five degrees with the sensitive plate. E is a larger reflector, in front of the object-glass C, also at an angle ot forty-live degrees with the sensitive plate, and two and a halt' or three inches fart-her fromthe sensitive plate than the reiiector D. rlhe two reflectors are ixed in the box or hood F, which can be attached to or detached from the front board; or they may be fixed in separate hoods7 which are att-ached to the front board, or to the lenstubes.

The reflectors majT be varied slightly from the angle offorty-ve degrees, so as to increase Fig. 2 is a or diminish the dist-ance between the two pic tures.

The camera is placed with the sensitive plate parallel with the principal ray. The

light from the/object which strikes the two ject, one object-glass should be one-haltl inch longer focus, if onc-twenty-fourth, one-fourth inch; it' one-forty-eighth, one-eighth inch, tc. .The focus of an object-glass may be lengthcned by using a slightly concave lens between the two lenses.

In taking negatives the film should be turned away from the lenses. I claim as my invention- The combination ot' one object-glass, having a reilector close in front of it, with another object-glass, having a larger retlector, two and one-halt' inches or more farther from the lens in front than the other, substantially as described, for the purpose of obviating the nccessity i'or traiisposition.

WIitnesses: WARREN HARRIS.

RUFUs AMES, EMERSON GUE. 

